If this is a practical question, would you consider something like vermicompost poop? Sure, it's gone through a worm, but at some point of tiny and low-energy that becomes pretty indistinguishable from microbial action.

Otherwise, yeah, plain old compost. There's still going to be microscopic worms in there, but I have no idea how much of it actually goes through their digestive tract, in the end.

Depends on exactly what nutrients your plants are missing. Your own Compost usually works well

Fish emulsion, plant compost.

People mine nutrients for industrial use, so yes.

fish guts, leafmold

Poop is natural. Just saying.
If you think about it, rotted or decomposed organic materials are basically insect, bacterium and mold poop...

Elaborating on why thats what you're looking for may help people give you more helpful answers that meet your needs :)

What about blood meal and bone meal? Still animal product but not poop. I'm still pretty new gardening, so not sure on effectiveness.

Not gonna pretend I'm an expert or anything, but

What about compost?

I think I've read that seaweed can be good too, but I'm not sure if that's more of an addition rather than a replacement

I'm pretty sure most fertilisers you get come from either animal waste or petrochemicals

Potash

Depending on what you consider natural and efficient.

If mining is natural there is some volcanic stuff that is nutrient rich. If by natural you mean organic, compost piles produce good fertilisers but they are not as efficient as some might say. They take quite some time to complete their process and get it's nutrients available for growing plants. Not being efficient doesn't mean they aren't good. They are a great way to dispose or organic material and even if compost releases its nutrients very slowly it contributes to the soil health in many other ways that I would say are more important, like increasing biodiversity, making the soil more resistant to changes in pH and facilitating retention of nutrients so they don't wash out with rain.

https://theownerbuildernetwork.co/gardens/2025/10/09/electroculture-gardening/

I literally learned about this less than an hour ago.

My friend was telling me that she's going to put some copper piping from an old fridge in her backyard garden.

Apparently, this has been a thing for centuries, and only stopped being popular when WW2 demanded all the scrap metal on hand.

fertilizers come in two types. industrial and nonindustrial.

industrial fertilizers are based on industrial processes that generate chemically pure product. this product is usually viewed similar to salts. salt is naturally found in soil, but too much can burn your soil. same thing for industrial fertilizers.

nonindustrial fertilizers are commonly derived. these would be based on "waste" products. not all of them are based on the fecal content, some are processed food wastes, animal waste(dead fish, pork, beef, etc). the process to derive the fertilizer basically speeds up the decomposition of naturally occurring materials found in the world.

you will have better long term results using nonindustrial fertilizer because it is easier for the soil biome to naturally break down the necessary components for plant life faster than industrial fertilizers. this allows the soil to rebound faster and toxicity to remain low.

industrial fertilizers tend to build up in the soil over time and turns the soil toxic inhibiting plant growth aka "burning".

unless you live in an extreme environment where it's impossible to grow plants, I would avoid industrial fertilizers.

personally I use the nonindustrial or organic fertilizer with much success.

Compost piles are a thing, idk how efficient they are vs manure. One of the reasons farmers use manure is they have so much of it anyways and it's got to go somewhere. There's also various plants that do similar work when planted in the soil, something about nitrogen fixing. Whether or not something is natural or not gets hard to define but there are ways of getting plants nutrients that are mostly not animal. I say mostly because it also depends on how you're defining that and how you store and handle things one what ends up inside it but I imagine a meticulous person could manage it.

The Plasma Channel just released a video about how water exposed to coronal discharge becomes an interesting sort of fertilizer.

If looking for poop alternatives.. it's something. Might be worth looking at aquaponics additives, probably the next alternative to poop is petrochemical though.

Like Polyhalite, for example?

In my personal experience if you have to pick one, animal manure (I count human poop under that as well) works better than compost from just plant material (like plant cuttings, kitchen waste, weeds, wood chip ...). Best is a mix of both.

Human poop, using it as fertilizer has historically been a thing in some regions. https://solar.lowtechmagazine.com/2010/09/recycling-animal-and-human-dung-is-the-key-to-sustainable-farming/

I remember growing up, my nan used to make nettle water, I hated the smell. Basically just chuck a bunch of nettle in water and let it macerate. You've been warned about the smell though!

I like to use a fish emulsion product. The brand available at several places where I am is "Alaska", there are probably other brands and you can even make it if you find yourself with a pile of leftover fish parts. It's generally 5-1-1 or 4-1-1, mostly nitrogen for green growth, and you just dilute it into water.